J&J’s guselkumab leads the race for first to market IL-23 inhibitor for psoriasis

On March 5, 2016, data on J&J’s guselkumab in patients with psoriasis and psoriatic arthritis were presented at the 75th Annual American Academy of Dermatology (AAD) meeting. Guselkumab is a human monoclonal antibody that binds specific to interleukin 23 (IL-23), which is involved in the pathophysiology of numerous chronic inflammatory diseases, including psoriasis and psoriatic arthritis. In November 2016, J&J submitted applications to the FDA and EMA for the approval of guselkumab for moderate-to-severe plaque psoriasis. If approved, guselkumab would be the first biologic to specifically target IL-23 to be indicated for psoriasis—giving the drug a first-to-market advantage. According to GlobalData, guselkumab is slated to become a blockbuster therapy, earning $1.1 billion in 2024 across the eight major pharmaceutical markets (8MM) — US, France, Germany, Italy, Spain, UK, Japan, and India) – in psoriasis alone.

In a Phase III, placebo- and active comparator-controlled, double-blind trial (VOYAGE 2), patients with moderate-to-severe psoriasis were randomized to receive 100mg of guselkumab at Weeks 0, 4, 12, and 20; 80mg of Humira at Week 0 followed by 40mg at Week 1, then 20mg every two weeks through Week 23; or placebo at Weeks 0, 4, and 12 followed by 100mg of guselkumab at Weeks 16 and 20. Both primary endpoints, the proportion of patients achieving Investigator’s Global Assessment score of cleared or minimal (IGA 0/1) and the proportion of patients achieving a Psoriasis Area and Severity Index (PASI) 90 response, as well as major secondary endpoints were met (p<0.001 for all endpoints).

At Week 16, guselkumab treated patients demonstrated a significantly higher proportion of patients achieving IGA 0/1 (84.1% compared with 8.5%), PASI 90 (70.1% compared with 2.4%), and Dermatology Life Quality Index (DLQI 0/1) compared with placebo. Patients treated with guselkumab also showed superiority of Humira treated patients in IGA 0/1 (84.1% compared with 67.7%), PASI 75 (86.3% compared with 68.5%), and PASI 90 (70.0% compared with 46.8%) at Week 16. In addition, 34.1% of patients treated with guselkumab reached PASI 100 score at Week 16 and most notably, maintained a PASI 100 response through Week 24. J&J conducted two additional Phase III studies evaluating guselkumab in psoriasis, VOYAGE 1 and 3, which also demonstrated positive results.     
Further, in a Phase IIa double-blind, placebo-controlled, multicenter study, 194 patients with psoriatic arthritis were randomized 2:1 to receive 100mg of guselkumab or placebo at Weeks 0 and 4, and then every eight weeks through Week 44. At Week 24, all patients in the placebo group were treated with 100mg guselkumab at Weeks 24 and 28 an then every eight weeks through Week 44. At Week 24, significantly more patients achieved ACR 20% improvement criteria (ACR20), the primary endpoint, compared with placebo (58.0% compared with 18.4%, p<0.001). In addition, significantly more patients treated with guselkumab reached secondary endpoints, including PASI 75 and ACR 50, compared with placebo (p<0.001 and p=0.002, respectively).

Positive Phase IIa data for guselkumab in psoriatic arthritis marks substantial opportunity for J&J, with the potential for label expansion and subsequent increased sales. Regardless of an approval in psoriatic arthritis, guselkumab is positioned to become a blockbuster therapy, given the drug’s desirable efficacy and safety profile in the psoriasis disease space.